The present invention relates generally to voltage generators. More particularly, the present invention relates to a method and apparatus to provide a low voltage reference generation.
A reference voltage generator is a device that is powered by an input voltage and outputs a reference voltage to compare with another voltage. Prior art reference voltage generators use constant voltage input for supplying power to the voltage reference generation circuit. The same constant voltage input is also used for generating the voltage reference.
A problem with this approach is that current technology devices supply different voltage values that vary with time. The current voltage reference generators are limited in their operation since they can only operate under one constant voltage value and need to be redesigned for a different voltage value. Another problem with using same constant voltage input for both supplying current to the circuit and generating a voltage reference is that it loads the voltage potential of the voltage input by having to perform two functions. This results in producing a voltage reference that varies highly with distribution of input voltage through the circuit.
Prior art reference voltage generators also provide a constant output reference voltage irrespective of changes to the input voltage. A problem with this approach is that it is only applicable to a very limited number of electronic devices that support the constant output reference voltage. Thus this approach may not be modified to apply to parts that do not accept the produced constant reference voltage.